xref: /linux/drivers/nvdimm/label.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  */
13 #include <linux/device.h>
14 #include <linux/ndctl.h>
15 #include <linux/uuid.h>
16 #include <linux/slab.h>
17 #include <linux/io.h>
18 #include <linux/nd.h>
19 #include "nd-core.h"
20 #include "label.h"
21 #include "nd.h"
22 
23 static guid_t nvdimm_btt_guid;
24 static guid_t nvdimm_btt2_guid;
25 static guid_t nvdimm_pfn_guid;
26 static guid_t nvdimm_dax_guid;
27 
28 static u32 best_seq(u32 a, u32 b)
29 {
30 	a &= NSINDEX_SEQ_MASK;
31 	b &= NSINDEX_SEQ_MASK;
32 
33 	if (a == 0 || a == b)
34 		return b;
35 	else if (b == 0)
36 		return a;
37 	else if (nd_inc_seq(a) == b)
38 		return b;
39 	else
40 		return a;
41 }
42 
43 unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
44 {
45 	return ndd->nslabel_size;
46 }
47 
48 int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
49 {
50 	return ndd->nsarea.config_size / (sizeof_namespace_label(ndd) + 1);
51 }
52 
53 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
54 {
55 	u32 nslot, space, size;
56 
57 	/*
58 	 * The minimum index space is 512 bytes, with that amount of
59 	 * index we can describe ~1400 labels which is less than a byte
60 	 * of overhead per label.  Round up to a byte of overhead per
61 	 * label and determine the size of the index region.  Yes, this
62 	 * starts to waste space at larger config_sizes, but it's
63 	 * unlikely we'll ever see anything but 128K.
64 	 */
65 	nslot = nvdimm_num_label_slots(ndd);
66 	space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
67 	size = ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
68 			NSINDEX_ALIGN) * 2;
69 	if (size <= space)
70 		return size / 2;
71 
72 	dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
73 			ndd->nsarea.config_size, sizeof_namespace_label(ndd));
74 	return 0;
75 }
76 
77 static int __nd_label_validate(struct nvdimm_drvdata *ndd)
78 {
79 	/*
80 	 * On media label format consists of two index blocks followed
81 	 * by an array of labels.  None of these structures are ever
82 	 * updated in place.  A sequence number tracks the current
83 	 * active index and the next one to write, while labels are
84 	 * written to free slots.
85 	 *
86 	 *     +------------+
87 	 *     |            |
88 	 *     |  nsindex0  |
89 	 *     |            |
90 	 *     +------------+
91 	 *     |            |
92 	 *     |  nsindex1  |
93 	 *     |            |
94 	 *     +------------+
95 	 *     |   label0   |
96 	 *     +------------+
97 	 *     |   label1   |
98 	 *     +------------+
99 	 *     |            |
100 	 *      ....nslot...
101 	 *     |            |
102 	 *     +------------+
103 	 *     |   labelN   |
104 	 *     +------------+
105 	 */
106 	struct nd_namespace_index *nsindex[] = {
107 		to_namespace_index(ndd, 0),
108 		to_namespace_index(ndd, 1),
109 	};
110 	const int num_index = ARRAY_SIZE(nsindex);
111 	struct device *dev = ndd->dev;
112 	bool valid[2] = { 0 };
113 	int i, num_valid = 0;
114 	u32 seq;
115 
116 	for (i = 0; i < num_index; i++) {
117 		u32 nslot;
118 		u8 sig[NSINDEX_SIG_LEN];
119 		u64 sum_save, sum, size;
120 		unsigned int version, labelsize;
121 
122 		memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
123 		if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
124 			dev_dbg(dev, "%s: nsindex%d signature invalid\n",
125 					__func__, i);
126 			continue;
127 		}
128 
129 		/* label sizes larger than 128 arrived with v1.2 */
130 		version = __le16_to_cpu(nsindex[i]->major) * 100
131 			+ __le16_to_cpu(nsindex[i]->minor);
132 		if (version >= 102)
133 			labelsize = 1 << (7 + nsindex[i]->labelsize);
134 		else
135 			labelsize = 128;
136 
137 		if (labelsize != sizeof_namespace_label(ndd)) {
138 			dev_dbg(dev, "%s: nsindex%d labelsize %d invalid\n",
139 					__func__, i, nsindex[i]->labelsize);
140 			continue;
141 		}
142 
143 		sum_save = __le64_to_cpu(nsindex[i]->checksum);
144 		nsindex[i]->checksum = __cpu_to_le64(0);
145 		sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
146 		nsindex[i]->checksum = __cpu_to_le64(sum_save);
147 		if (sum != sum_save) {
148 			dev_dbg(dev, "%s: nsindex%d checksum invalid\n",
149 					__func__, i);
150 			continue;
151 		}
152 
153 		seq = __le32_to_cpu(nsindex[i]->seq);
154 		if ((seq & NSINDEX_SEQ_MASK) == 0) {
155 			dev_dbg(dev, "%s: nsindex%d sequence: %#x invalid\n",
156 					__func__, i, seq);
157 			continue;
158 		}
159 
160 		/* sanity check the index against expected values */
161 		if (__le64_to_cpu(nsindex[i]->myoff)
162 				!= i * sizeof_namespace_index(ndd)) {
163 			dev_dbg(dev, "%s: nsindex%d myoff: %#llx invalid\n",
164 					__func__, i, (unsigned long long)
165 					__le64_to_cpu(nsindex[i]->myoff));
166 			continue;
167 		}
168 		if (__le64_to_cpu(nsindex[i]->otheroff)
169 				!= (!i) * sizeof_namespace_index(ndd)) {
170 			dev_dbg(dev, "%s: nsindex%d otheroff: %#llx invalid\n",
171 					__func__, i, (unsigned long long)
172 					__le64_to_cpu(nsindex[i]->otheroff));
173 			continue;
174 		}
175 
176 		size = __le64_to_cpu(nsindex[i]->mysize);
177 		if (size > sizeof_namespace_index(ndd)
178 				|| size < sizeof(struct nd_namespace_index)) {
179 			dev_dbg(dev, "%s: nsindex%d mysize: %#llx invalid\n",
180 					__func__, i, size);
181 			continue;
182 		}
183 
184 		nslot = __le32_to_cpu(nsindex[i]->nslot);
185 		if (nslot * sizeof_namespace_label(ndd)
186 				+ 2 * sizeof_namespace_index(ndd)
187 				> ndd->nsarea.config_size) {
188 			dev_dbg(dev, "%s: nsindex%d nslot: %u invalid, config_size: %#x\n",
189 					__func__, i, nslot,
190 					ndd->nsarea.config_size);
191 			continue;
192 		}
193 		valid[i] = true;
194 		num_valid++;
195 	}
196 
197 	switch (num_valid) {
198 	case 0:
199 		break;
200 	case 1:
201 		for (i = 0; i < num_index; i++)
202 			if (valid[i])
203 				return i;
204 		/* can't have num_valid > 0 but valid[] = { false, false } */
205 		WARN_ON(1);
206 		break;
207 	default:
208 		/* pick the best index... */
209 		seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
210 				__le32_to_cpu(nsindex[1]->seq));
211 		if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
212 			return 1;
213 		else
214 			return 0;
215 		break;
216 	}
217 
218 	return -1;
219 }
220 
221 int nd_label_validate(struct nvdimm_drvdata *ndd)
222 {
223 	/*
224 	 * In order to probe for and validate namespace index blocks we
225 	 * need to know the size of the labels, and we can't trust the
226 	 * size of the labels until we validate the index blocks.
227 	 * Resolve this dependency loop by probing for known label
228 	 * sizes, but default to v1.2 256-byte namespace labels if
229 	 * discovery fails.
230 	 */
231 	int label_size[] = { 128, 256 };
232 	int i, rc;
233 
234 	for (i = 0; i < ARRAY_SIZE(label_size); i++) {
235 		ndd->nslabel_size = label_size[i];
236 		rc = __nd_label_validate(ndd);
237 		if (rc >= 0)
238 			return rc;
239 	}
240 
241 	return -1;
242 }
243 
244 void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
245 		struct nd_namespace_index *src)
246 {
247 	if (dst && src)
248 		/* pass */;
249 	else
250 		return;
251 
252 	memcpy(dst, src, sizeof_namespace_index(ndd));
253 }
254 
255 static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
256 {
257 	void *base = to_namespace_index(ndd, 0);
258 
259 	return base + 2 * sizeof_namespace_index(ndd);
260 }
261 
262 static int to_slot(struct nvdimm_drvdata *ndd,
263 		struct nd_namespace_label *nd_label)
264 {
265 	unsigned long label, base;
266 
267 	label = (unsigned long) nd_label;
268 	base = (unsigned long) nd_label_base(ndd);
269 
270 	return (label - base) / sizeof_namespace_label(ndd);
271 }
272 
273 static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
274 {
275 	unsigned long label, base;
276 
277 	base = (unsigned long) nd_label_base(ndd);
278 	label = base + sizeof_namespace_label(ndd) * slot;
279 
280 	return (struct nd_namespace_label *) label;
281 }
282 
283 #define for_each_clear_bit_le(bit, addr, size) \
284 	for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
285 	     (bit) < (size);                                    \
286 	     (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
287 
288 /**
289  * preamble_index - common variable initialization for nd_label_* routines
290  * @ndd: dimm container for the relevant label set
291  * @idx: namespace_index index
292  * @nsindex_out: on return set to the currently active namespace index
293  * @free: on return set to the free label bitmap in the index
294  * @nslot: on return set to the number of slots in the label space
295  */
296 static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
297 		struct nd_namespace_index **nsindex_out,
298 		unsigned long **free, u32 *nslot)
299 {
300 	struct nd_namespace_index *nsindex;
301 
302 	nsindex = to_namespace_index(ndd, idx);
303 	if (nsindex == NULL)
304 		return false;
305 
306 	*free = (unsigned long *) nsindex->free;
307 	*nslot = __le32_to_cpu(nsindex->nslot);
308 	*nsindex_out = nsindex;
309 
310 	return true;
311 }
312 
313 char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
314 {
315 	if (!label_id || !uuid)
316 		return NULL;
317 	snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb",
318 			flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid);
319 	return label_id->id;
320 }
321 
322 static bool preamble_current(struct nvdimm_drvdata *ndd,
323 		struct nd_namespace_index **nsindex,
324 		unsigned long **free, u32 *nslot)
325 {
326 	return preamble_index(ndd, ndd->ns_current, nsindex,
327 			free, nslot);
328 }
329 
330 static bool preamble_next(struct nvdimm_drvdata *ndd,
331 		struct nd_namespace_index **nsindex,
332 		unsigned long **free, u32 *nslot)
333 {
334 	return preamble_index(ndd, ndd->ns_next, nsindex,
335 			free, nslot);
336 }
337 
338 static bool slot_valid(struct nvdimm_drvdata *ndd,
339 		struct nd_namespace_label *nd_label, u32 slot)
340 {
341 	/* check that we are written where we expect to be written */
342 	if (slot != __le32_to_cpu(nd_label->slot))
343 		return false;
344 
345 	/* check that DPA allocations are page aligned */
346 	if ((__le64_to_cpu(nd_label->dpa)
347 				| __le64_to_cpu(nd_label->rawsize)) % SZ_4K)
348 		return false;
349 
350 	/* check checksum */
351 	if (namespace_label_has(ndd, checksum)) {
352 		u64 sum, sum_save;
353 
354 		sum_save = __le64_to_cpu(nd_label->checksum);
355 		nd_label->checksum = __cpu_to_le64(0);
356 		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
357 		nd_label->checksum = __cpu_to_le64(sum_save);
358 		if (sum != sum_save) {
359 			dev_dbg(ndd->dev, "%s fail checksum. slot: %d expect: %#llx\n",
360 				__func__, slot, sum);
361 			return false;
362 		}
363 	}
364 
365 	return true;
366 }
367 
368 int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
369 {
370 	struct nd_namespace_index *nsindex;
371 	unsigned long *free;
372 	u32 nslot, slot;
373 
374 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
375 		return 0; /* no label, nothing to reserve */
376 
377 	for_each_clear_bit_le(slot, free, nslot) {
378 		struct nd_namespace_label *nd_label;
379 		struct nd_region *nd_region = NULL;
380 		u8 label_uuid[NSLABEL_UUID_LEN];
381 		struct nd_label_id label_id;
382 		struct resource *res;
383 		u32 flags;
384 
385 		nd_label = to_label(ndd, slot);
386 
387 		if (!slot_valid(ndd, nd_label, slot))
388 			continue;
389 
390 		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
391 		flags = __le32_to_cpu(nd_label->flags);
392 		nd_label_gen_id(&label_id, label_uuid, flags);
393 		res = nvdimm_allocate_dpa(ndd, &label_id,
394 				__le64_to_cpu(nd_label->dpa),
395 				__le64_to_cpu(nd_label->rawsize));
396 		nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
397 		if (!res)
398 			return -EBUSY;
399 	}
400 
401 	return 0;
402 }
403 
404 int nd_label_active_count(struct nvdimm_drvdata *ndd)
405 {
406 	struct nd_namespace_index *nsindex;
407 	unsigned long *free;
408 	u32 nslot, slot;
409 	int count = 0;
410 
411 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
412 		return 0;
413 
414 	for_each_clear_bit_le(slot, free, nslot) {
415 		struct nd_namespace_label *nd_label;
416 
417 		nd_label = to_label(ndd, slot);
418 
419 		if (!slot_valid(ndd, nd_label, slot)) {
420 			u32 label_slot = __le32_to_cpu(nd_label->slot);
421 			u64 size = __le64_to_cpu(nd_label->rawsize);
422 			u64 dpa = __le64_to_cpu(nd_label->dpa);
423 
424 			dev_dbg(ndd->dev,
425 				"%s: slot%d invalid slot: %d dpa: %llx size: %llx\n",
426 					__func__, slot, label_slot, dpa, size);
427 			continue;
428 		}
429 		count++;
430 	}
431 	return count;
432 }
433 
434 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
435 {
436 	struct nd_namespace_index *nsindex;
437 	unsigned long *free;
438 	u32 nslot, slot;
439 
440 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
441 		return NULL;
442 
443 	for_each_clear_bit_le(slot, free, nslot) {
444 		struct nd_namespace_label *nd_label;
445 
446 		nd_label = to_label(ndd, slot);
447 		if (!slot_valid(ndd, nd_label, slot))
448 			continue;
449 
450 		if (n-- == 0)
451 			return to_label(ndd, slot);
452 	}
453 
454 	return NULL;
455 }
456 
457 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
458 {
459 	struct nd_namespace_index *nsindex;
460 	unsigned long *free;
461 	u32 nslot, slot;
462 
463 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
464 		return UINT_MAX;
465 
466 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
467 
468 	slot = find_next_bit_le(free, nslot, 0);
469 	if (slot == nslot)
470 		return UINT_MAX;
471 
472 	clear_bit_le(slot, free);
473 
474 	return slot;
475 }
476 
477 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
478 {
479 	struct nd_namespace_index *nsindex;
480 	unsigned long *free;
481 	u32 nslot;
482 
483 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
484 		return false;
485 
486 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
487 
488 	if (slot < nslot)
489 		return !test_and_set_bit_le(slot, free);
490 	return false;
491 }
492 
493 u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
494 {
495 	struct nd_namespace_index *nsindex;
496 	unsigned long *free;
497 	u32 nslot;
498 
499 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
500 
501 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
502 		return nvdimm_num_label_slots(ndd);
503 
504 	return bitmap_weight(free, nslot);
505 }
506 
507 static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
508 		unsigned long flags)
509 {
510 	struct nd_namespace_index *nsindex;
511 	unsigned long offset;
512 	u64 checksum;
513 	u32 nslot;
514 	int rc;
515 
516 	nsindex = to_namespace_index(ndd, index);
517 	if (flags & ND_NSINDEX_INIT)
518 		nslot = nvdimm_num_label_slots(ndd);
519 	else
520 		nslot = __le32_to_cpu(nsindex->nslot);
521 
522 	memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
523 	memset(&nsindex->flags, 0, 3);
524 	nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
525 	nsindex->seq = __cpu_to_le32(seq);
526 	offset = (unsigned long) nsindex
527 		- (unsigned long) to_namespace_index(ndd, 0);
528 	nsindex->myoff = __cpu_to_le64(offset);
529 	nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
530 	offset = (unsigned long) to_namespace_index(ndd,
531 			nd_label_next_nsindex(index))
532 		- (unsigned long) to_namespace_index(ndd, 0);
533 	nsindex->otheroff = __cpu_to_le64(offset);
534 	offset = (unsigned long) nd_label_base(ndd)
535 		- (unsigned long) to_namespace_index(ndd, 0);
536 	nsindex->labeloff = __cpu_to_le64(offset);
537 	nsindex->nslot = __cpu_to_le32(nslot);
538 	nsindex->major = __cpu_to_le16(1);
539 	if (sizeof_namespace_label(ndd) < 256)
540 		nsindex->minor = __cpu_to_le16(1);
541 	else
542 		nsindex->minor = __cpu_to_le16(2);
543 	nsindex->checksum = __cpu_to_le64(0);
544 	if (flags & ND_NSINDEX_INIT) {
545 		unsigned long *free = (unsigned long *) nsindex->free;
546 		u32 nfree = ALIGN(nslot, BITS_PER_LONG);
547 		int last_bits, i;
548 
549 		memset(nsindex->free, 0xff, nfree / 8);
550 		for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
551 			clear_bit_le(nslot + i, free);
552 	}
553 	checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
554 	nsindex->checksum = __cpu_to_le64(checksum);
555 	rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
556 			nsindex, sizeof_namespace_index(ndd));
557 	if (rc < 0)
558 		return rc;
559 
560 	if (flags & ND_NSINDEX_INIT)
561 		return 0;
562 
563 	/* copy the index we just wrote to the new 'next' */
564 	WARN_ON(index != ndd->ns_next);
565 	nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
566 	ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
567 	ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
568 	WARN_ON(ndd->ns_current == ndd->ns_next);
569 
570 	return 0;
571 }
572 
573 static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
574 		struct nd_namespace_label *nd_label)
575 {
576 	return (unsigned long) nd_label
577 		- (unsigned long) to_namespace_index(ndd, 0);
578 }
579 
580 enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
581 {
582 	if (guid_equal(guid, &nvdimm_btt_guid))
583 		return NVDIMM_CCLASS_BTT;
584 	else if (guid_equal(guid, &nvdimm_btt2_guid))
585 		return NVDIMM_CCLASS_BTT2;
586 	else if (guid_equal(guid, &nvdimm_pfn_guid))
587 		return NVDIMM_CCLASS_PFN;
588 	else if (guid_equal(guid, &nvdimm_dax_guid))
589 		return NVDIMM_CCLASS_DAX;
590 	else if (guid_equal(guid, &guid_null))
591 		return NVDIMM_CCLASS_NONE;
592 
593 	return NVDIMM_CCLASS_UNKNOWN;
594 }
595 
596 static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
597 	guid_t *target)
598 {
599 	if (claim_class == NVDIMM_CCLASS_BTT)
600 		return &nvdimm_btt_guid;
601 	else if (claim_class == NVDIMM_CCLASS_BTT2)
602 		return &nvdimm_btt2_guid;
603 	else if (claim_class == NVDIMM_CCLASS_PFN)
604 		return &nvdimm_pfn_guid;
605 	else if (claim_class == NVDIMM_CCLASS_DAX)
606 		return &nvdimm_dax_guid;
607 	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
608 		/*
609 		 * If we're modifying a namespace for which we don't
610 		 * know the claim_class, don't touch the existing guid.
611 		 */
612 		return target;
613 	} else
614 		return &guid_null;
615 }
616 
617 static int __pmem_label_update(struct nd_region *nd_region,
618 		struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
619 		int pos)
620 {
621 	struct nd_namespace_common *ndns = &nspm->nsio.common;
622 	struct nd_interleave_set *nd_set = nd_region->nd_set;
623 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
624 	struct nd_label_ent *label_ent, *victim = NULL;
625 	struct nd_namespace_label *nd_label;
626 	struct nd_namespace_index *nsindex;
627 	struct nd_label_id label_id;
628 	struct resource *res;
629 	unsigned long *free;
630 	u32 nslot, slot;
631 	size_t offset;
632 	u64 cookie;
633 	int rc;
634 
635 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
636 		return -ENXIO;
637 
638 	cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
639 	nd_label_gen_id(&label_id, nspm->uuid, 0);
640 	for_each_dpa_resource(ndd, res)
641 		if (strcmp(res->name, label_id.id) == 0)
642 			break;
643 
644 	if (!res) {
645 		WARN_ON_ONCE(1);
646 		return -ENXIO;
647 	}
648 
649 	/* allocate and write the label to the staging (next) index */
650 	slot = nd_label_alloc_slot(ndd);
651 	if (slot == UINT_MAX)
652 		return -ENXIO;
653 	dev_dbg(ndd->dev, "%s: allocated: %d\n", __func__, slot);
654 
655 	nd_label = to_label(ndd, slot);
656 	memset(nd_label, 0, sizeof_namespace_label(ndd));
657 	memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
658 	if (nspm->alt_name)
659 		memcpy(nd_label->name, nspm->alt_name, NSLABEL_NAME_LEN);
660 	nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_UPDATING);
661 	nd_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
662 	nd_label->position = __cpu_to_le16(pos);
663 	nd_label->isetcookie = __cpu_to_le64(cookie);
664 	nd_label->rawsize = __cpu_to_le64(resource_size(res));
665 	nd_label->lbasize = __cpu_to_le64(nspm->lbasize);
666 	nd_label->dpa = __cpu_to_le64(res->start);
667 	nd_label->slot = __cpu_to_le32(slot);
668 	if (namespace_label_has(ndd, type_guid))
669 		guid_copy(&nd_label->type_guid, &nd_set->type_guid);
670 	if (namespace_label_has(ndd, abstraction_guid))
671 		guid_copy(&nd_label->abstraction_guid,
672 				to_abstraction_guid(ndns->claim_class,
673 					&nd_label->abstraction_guid));
674 	if (namespace_label_has(ndd, checksum)) {
675 		u64 sum;
676 
677 		nd_label->checksum = __cpu_to_le64(0);
678 		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
679 		nd_label->checksum = __cpu_to_le64(sum);
680 	}
681 	nd_dbg_dpa(nd_region, ndd, res, "%s\n", __func__);
682 
683 	/* update label */
684 	offset = nd_label_offset(ndd, nd_label);
685 	rc = nvdimm_set_config_data(ndd, offset, nd_label,
686 			sizeof_namespace_label(ndd));
687 	if (rc < 0)
688 		return rc;
689 
690 	/* Garbage collect the previous label */
691 	mutex_lock(&nd_mapping->lock);
692 	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
693 		if (!label_ent->label)
694 			continue;
695 		if (memcmp(nspm->uuid, label_ent->label->uuid,
696 					NSLABEL_UUID_LEN) != 0)
697 			continue;
698 		victim = label_ent;
699 		list_move_tail(&victim->list, &nd_mapping->labels);
700 		break;
701 	}
702 	if (victim) {
703 		dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
704 		slot = to_slot(ndd, victim->label);
705 		nd_label_free_slot(ndd, slot);
706 		victim->label = NULL;
707 	}
708 
709 	/* update index */
710 	rc = nd_label_write_index(ndd, ndd->ns_next,
711 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
712 	if (rc == 0) {
713 		list_for_each_entry(label_ent, &nd_mapping->labels, list)
714 			if (!label_ent->label) {
715 				label_ent->label = nd_label;
716 				nd_label = NULL;
717 				break;
718 			}
719 		dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
720 				"failed to track label: %d\n",
721 				to_slot(ndd, nd_label));
722 		if (nd_label)
723 			rc = -ENXIO;
724 	}
725 	mutex_unlock(&nd_mapping->lock);
726 
727 	return rc;
728 }
729 
730 static bool is_old_resource(struct resource *res, struct resource **list, int n)
731 {
732 	int i;
733 
734 	if (res->flags & DPA_RESOURCE_ADJUSTED)
735 		return false;
736 	for (i = 0; i < n; i++)
737 		if (res == list[i])
738 			return true;
739 	return false;
740 }
741 
742 static struct resource *to_resource(struct nvdimm_drvdata *ndd,
743 		struct nd_namespace_label *nd_label)
744 {
745 	struct resource *res;
746 
747 	for_each_dpa_resource(ndd, res) {
748 		if (res->start != __le64_to_cpu(nd_label->dpa))
749 			continue;
750 		if (resource_size(res) != __le64_to_cpu(nd_label->rawsize))
751 			continue;
752 		return res;
753 	}
754 
755 	return NULL;
756 }
757 
758 /*
759  * 1/ Account all the labels that can be freed after this update
760  * 2/ Allocate and write the label to the staging (next) index
761  * 3/ Record the resources in the namespace device
762  */
763 static int __blk_label_update(struct nd_region *nd_region,
764 		struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
765 		int num_labels)
766 {
767 	int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
768 	struct nd_interleave_set *nd_set = nd_region->nd_set;
769 	struct nd_namespace_common *ndns = &nsblk->common;
770 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
771 	struct nd_namespace_label *nd_label;
772 	struct nd_label_ent *label_ent, *e;
773 	struct nd_namespace_index *nsindex;
774 	unsigned long *free, *victim_map = NULL;
775 	struct resource *res, **old_res_list;
776 	struct nd_label_id label_id;
777 	u8 uuid[NSLABEL_UUID_LEN];
778 	int min_dpa_idx = 0;
779 	LIST_HEAD(list);
780 	u32 nslot, slot;
781 
782 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
783 		return -ENXIO;
784 
785 	old_res_list = nsblk->res;
786 	nfree = nd_label_nfree(ndd);
787 	old_num_resources = nsblk->num_resources;
788 	nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
789 
790 	/*
791 	 * We need to loop over the old resources a few times, which seems a
792 	 * bit inefficient, but we need to know that we have the label
793 	 * space before we start mutating the tracking structures.
794 	 * Otherwise the recovery method of last resort for userspace is
795 	 * disable and re-enable the parent region.
796 	 */
797 	alloc = 0;
798 	for_each_dpa_resource(ndd, res) {
799 		if (strcmp(res->name, label_id.id) != 0)
800 			continue;
801 		if (!is_old_resource(res, old_res_list, old_num_resources))
802 			alloc++;
803 	}
804 
805 	victims = 0;
806 	if (old_num_resources) {
807 		/* convert old local-label-map to dimm-slot victim-map */
808 		victim_map = kcalloc(BITS_TO_LONGS(nslot), sizeof(long),
809 				GFP_KERNEL);
810 		if (!victim_map)
811 			return -ENOMEM;
812 
813 		/* mark unused labels for garbage collection */
814 		for_each_clear_bit_le(slot, free, nslot) {
815 			nd_label = to_label(ndd, slot);
816 			memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
817 			if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
818 				continue;
819 			res = to_resource(ndd, nd_label);
820 			if (res && is_old_resource(res, old_res_list,
821 						old_num_resources))
822 				continue;
823 			slot = to_slot(ndd, nd_label);
824 			set_bit(slot, victim_map);
825 			victims++;
826 		}
827 	}
828 
829 	/* don't allow updates that consume the last label */
830 	if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
831 		dev_info(&nsblk->common.dev, "insufficient label space\n");
832 		kfree(victim_map);
833 		return -ENOSPC;
834 	}
835 	/* from here on we need to abort on error */
836 
837 
838 	/* assign all resources to the namespace before writing the labels */
839 	nsblk->res = NULL;
840 	nsblk->num_resources = 0;
841 	for_each_dpa_resource(ndd, res) {
842 		if (strcmp(res->name, label_id.id) != 0)
843 			continue;
844 		if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
845 			rc = -ENOMEM;
846 			goto abort;
847 		}
848 	}
849 
850 	/*
851 	 * Find the resource associated with the first label in the set
852 	 * per the v1.2 namespace specification.
853 	 */
854 	for (i = 0; i < nsblk->num_resources; i++) {
855 		struct resource *min = nsblk->res[min_dpa_idx];
856 
857 		res = nsblk->res[i];
858 		if (res->start < min->start)
859 			min_dpa_idx = i;
860 	}
861 
862 	for (i = 0; i < nsblk->num_resources; i++) {
863 		size_t offset;
864 
865 		res = nsblk->res[i];
866 		if (is_old_resource(res, old_res_list, old_num_resources))
867 			continue; /* carry-over */
868 		slot = nd_label_alloc_slot(ndd);
869 		if (slot == UINT_MAX)
870 			goto abort;
871 		dev_dbg(ndd->dev, "%s: allocated: %d\n", __func__, slot);
872 
873 		nd_label = to_label(ndd, slot);
874 		memset(nd_label, 0, sizeof_namespace_label(ndd));
875 		memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
876 		if (nsblk->alt_name)
877 			memcpy(nd_label->name, nsblk->alt_name,
878 					NSLABEL_NAME_LEN);
879 		nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_LOCAL);
880 
881 		/*
882 		 * Use the presence of the type_guid as a flag to
883 		 * determine isetcookie usage and nlabel + position
884 		 * policy for blk-aperture namespaces.
885 		 */
886 		if (namespace_label_has(ndd, type_guid)) {
887 			if (i == min_dpa_idx) {
888 				nd_label->nlabel = __cpu_to_le16(nsblk->num_resources);
889 				nd_label->position = __cpu_to_le16(0);
890 			} else {
891 				nd_label->nlabel = __cpu_to_le16(0xffff);
892 				nd_label->position = __cpu_to_le16(0xffff);
893 			}
894 			nd_label->isetcookie = __cpu_to_le64(nd_set->cookie2);
895 		} else {
896 			nd_label->nlabel = __cpu_to_le16(0); /* N/A */
897 			nd_label->position = __cpu_to_le16(0); /* N/A */
898 			nd_label->isetcookie = __cpu_to_le64(0); /* N/A */
899 		}
900 
901 		nd_label->dpa = __cpu_to_le64(res->start);
902 		nd_label->rawsize = __cpu_to_le64(resource_size(res));
903 		nd_label->lbasize = __cpu_to_le64(nsblk->lbasize);
904 		nd_label->slot = __cpu_to_le32(slot);
905 		if (namespace_label_has(ndd, type_guid))
906 			guid_copy(&nd_label->type_guid, &nd_set->type_guid);
907 		if (namespace_label_has(ndd, abstraction_guid))
908 			guid_copy(&nd_label->abstraction_guid,
909 					to_abstraction_guid(ndns->claim_class,
910 						&nd_label->abstraction_guid));
911 
912 		if (namespace_label_has(ndd, checksum)) {
913 			u64 sum;
914 
915 			nd_label->checksum = __cpu_to_le64(0);
916 			sum = nd_fletcher64(nd_label,
917 					sizeof_namespace_label(ndd), 1);
918 			nd_label->checksum = __cpu_to_le64(sum);
919 		}
920 
921 		/* update label */
922 		offset = nd_label_offset(ndd, nd_label);
923 		rc = nvdimm_set_config_data(ndd, offset, nd_label,
924 				sizeof_namespace_label(ndd));
925 		if (rc < 0)
926 			goto abort;
927 	}
928 
929 	/* free up now unused slots in the new index */
930 	for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
931 		dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
932 		nd_label_free_slot(ndd, slot);
933 	}
934 
935 	/* update index */
936 	rc = nd_label_write_index(ndd, ndd->ns_next,
937 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
938 	if (rc)
939 		goto abort;
940 
941 	/*
942 	 * Now that the on-dimm labels are up to date, fix up the tracking
943 	 * entries in nd_mapping->labels
944 	 */
945 	nlabel = 0;
946 	mutex_lock(&nd_mapping->lock);
947 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
948 		nd_label = label_ent->label;
949 		if (!nd_label)
950 			continue;
951 		nlabel++;
952 		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
953 		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
954 			continue;
955 		nlabel--;
956 		list_move(&label_ent->list, &list);
957 		label_ent->label = NULL;
958 	}
959 	list_splice_tail_init(&list, &nd_mapping->labels);
960 	mutex_unlock(&nd_mapping->lock);
961 
962 	if (nlabel + nsblk->num_resources > num_labels) {
963 		/*
964 		 * Bug, we can't end up with more resources than
965 		 * available labels
966 		 */
967 		WARN_ON_ONCE(1);
968 		rc = -ENXIO;
969 		goto out;
970 	}
971 
972 	mutex_lock(&nd_mapping->lock);
973 	label_ent = list_first_entry_or_null(&nd_mapping->labels,
974 			typeof(*label_ent), list);
975 	if (!label_ent) {
976 		WARN_ON(1);
977 		mutex_unlock(&nd_mapping->lock);
978 		rc = -ENXIO;
979 		goto out;
980 	}
981 	for_each_clear_bit_le(slot, free, nslot) {
982 		nd_label = to_label(ndd, slot);
983 		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
984 		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
985 			continue;
986 		res = to_resource(ndd, nd_label);
987 		res->flags &= ~DPA_RESOURCE_ADJUSTED;
988 		dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
989 		list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
990 			if (label_ent->label)
991 				continue;
992 			label_ent->label = nd_label;
993 			nd_label = NULL;
994 			break;
995 		}
996 		if (nd_label)
997 			dev_WARN(&nsblk->common.dev,
998 					"failed to track label slot%d\n", slot);
999 	}
1000 	mutex_unlock(&nd_mapping->lock);
1001 
1002  out:
1003 	kfree(old_res_list);
1004 	kfree(victim_map);
1005 	return rc;
1006 
1007  abort:
1008 	/*
1009 	 * 1/ repair the allocated label bitmap in the index
1010 	 * 2/ restore the resource list
1011 	 */
1012 	nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
1013 	kfree(nsblk->res);
1014 	nsblk->res = old_res_list;
1015 	nsblk->num_resources = old_num_resources;
1016 	old_res_list = NULL;
1017 	goto out;
1018 }
1019 
1020 static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
1021 {
1022 	int i, old_num_labels = 0;
1023 	struct nd_label_ent *label_ent;
1024 	struct nd_namespace_index *nsindex;
1025 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1026 
1027 	mutex_lock(&nd_mapping->lock);
1028 	list_for_each_entry(label_ent, &nd_mapping->labels, list)
1029 		old_num_labels++;
1030 	mutex_unlock(&nd_mapping->lock);
1031 
1032 	/*
1033 	 * We need to preserve all the old labels for the mapping so
1034 	 * they can be garbage collected after writing the new labels.
1035 	 */
1036 	for (i = old_num_labels; i < num_labels; i++) {
1037 		label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
1038 		if (!label_ent)
1039 			return -ENOMEM;
1040 		mutex_lock(&nd_mapping->lock);
1041 		list_add_tail(&label_ent->list, &nd_mapping->labels);
1042 		mutex_unlock(&nd_mapping->lock);
1043 	}
1044 
1045 	if (ndd->ns_current == -1 || ndd->ns_next == -1)
1046 		/* pass */;
1047 	else
1048 		return max(num_labels, old_num_labels);
1049 
1050 	nsindex = to_namespace_index(ndd, 0);
1051 	memset(nsindex, 0, ndd->nsarea.config_size);
1052 	for (i = 0; i < 2; i++) {
1053 		int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
1054 
1055 		if (rc)
1056 			return rc;
1057 	}
1058 	ndd->ns_next = 1;
1059 	ndd->ns_current = 0;
1060 
1061 	return max(num_labels, old_num_labels);
1062 }
1063 
1064 static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
1065 {
1066 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1067 	struct nd_label_ent *label_ent, *e;
1068 	struct nd_namespace_index *nsindex;
1069 	u8 label_uuid[NSLABEL_UUID_LEN];
1070 	unsigned long *free;
1071 	LIST_HEAD(list);
1072 	u32 nslot, slot;
1073 	int active = 0;
1074 
1075 	if (!uuid)
1076 		return 0;
1077 
1078 	/* no index || no labels == nothing to delete */
1079 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
1080 		return 0;
1081 
1082 	mutex_lock(&nd_mapping->lock);
1083 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
1084 		struct nd_namespace_label *nd_label = label_ent->label;
1085 
1086 		if (!nd_label)
1087 			continue;
1088 		active++;
1089 		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
1090 		if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
1091 			continue;
1092 		active--;
1093 		slot = to_slot(ndd, nd_label);
1094 		nd_label_free_slot(ndd, slot);
1095 		dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
1096 		list_move_tail(&label_ent->list, &list);
1097 		label_ent->label = NULL;
1098 	}
1099 	list_splice_tail_init(&list, &nd_mapping->labels);
1100 
1101 	if (active == 0) {
1102 		nd_mapping_free_labels(nd_mapping);
1103 		dev_dbg(ndd->dev, "%s: no more active labels\n", __func__);
1104 	}
1105 	mutex_unlock(&nd_mapping->lock);
1106 
1107 	return nd_label_write_index(ndd, ndd->ns_next,
1108 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
1109 }
1110 
1111 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
1112 		struct nd_namespace_pmem *nspm, resource_size_t size)
1113 {
1114 	int i;
1115 
1116 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1117 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1118 		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1119 		struct resource *res;
1120 		int rc, count = 0;
1121 
1122 		if (size == 0) {
1123 			rc = del_labels(nd_mapping, nspm->uuid);
1124 			if (rc)
1125 				return rc;
1126 			continue;
1127 		}
1128 
1129 		for_each_dpa_resource(ndd, res)
1130 			if (strncmp(res->name, "pmem", 4) == 0)
1131 				count++;
1132 		WARN_ON_ONCE(!count);
1133 
1134 		rc = init_labels(nd_mapping, count);
1135 		if (rc < 0)
1136 			return rc;
1137 
1138 		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i);
1139 		if (rc)
1140 			return rc;
1141 	}
1142 
1143 	return 0;
1144 }
1145 
1146 int nd_blk_namespace_label_update(struct nd_region *nd_region,
1147 		struct nd_namespace_blk *nsblk, resource_size_t size)
1148 {
1149 	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
1150 	struct resource *res;
1151 	int count = 0;
1152 
1153 	if (size == 0)
1154 		return del_labels(nd_mapping, nsblk->uuid);
1155 
1156 	for_each_dpa_resource(to_ndd(nd_mapping), res)
1157 		count++;
1158 
1159 	count = init_labels(nd_mapping, count);
1160 	if (count < 0)
1161 		return count;
1162 
1163 	return __blk_label_update(nd_region, nd_mapping, nsblk, count);
1164 }
1165 
1166 int __init nd_label_init(void)
1167 {
1168 	WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
1169 	WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
1170 	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
1171 	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
1172 
1173 	return 0;
1174 }
1175